Add Needed Forward Declaration

content/renderer/media/android/webmediaplayer_android.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_RENDERER_MEDIA_ANDROID_WEBMEDIAPLAYER_ANDROID_H_
 #define CONTENT_RENDERER_MEDIA_ANDROID_WEBMEDIAPLAYER_ANDROID_H_
 
 #include <jni.h>
 #include <string>
 #include <vector>
@@ skipping 27 matching lines @@
 #include "ui/gfx/rect_f.h"
 
 namespace base {
 class SingleThreadTaskRunner;
 }
 
 namespace blink {
 class WebContentDecryptionModule;
 class WebContentDecryptionModuleResult;
 class WebFrame;
+class WebMediaPlayerClient;
 class WebURL;
 }
 
 namespace cc_blink {
 class WebLayerImpl;
 }
 
 namespace gpu {
 struct MailboxHolder;
 }
@@ skipping 441 matching lines @@
 
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<WebMediaPlayerAndroid> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMediaPlayerAndroid);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_ANDROID_WEBMEDIAPLAYER_ANDROID_H_